'Self-importance'

"We say that responsibility lies not as a result of any mental illness but we say as a result of her personality."

Ms Laing said Ms Donnison was not married to the children's father, Paul Donnison, but had changed her name by deed poll.

She claims to have no memory at all of the events that led to the killing of Harry and EliseChristine Laing QC, Crown Prosecution Service

She said the defendant was a narcissist with an overdeveloped sense of self importance, who often exhibited highly manipulative behaviour.

Ms Laing said the couple's relationship was strained, which was exacerbated by issues concerning Ms Donnison's two teenage sons who lived with them.

Ms Donnison had enjoyed a successful career in financial services in the City, but was made redundant in July 2009.

On 1 September 2009, the day after returning from a family holiday to Ireland, Mr Donnison came home from work to find the defendant had moved out, taking all four children with her.

The court heard she had left a note saying "for the sake of the children I feel I have no choice but to move out... I'm sorry, Fiona".

She would not tell him where she had gone at first but he later found out she had moved into a house in Lightwater, Surrey, 100 yards from where his first wife lived with their two children.

Ms Laing said the two children were last seen alive on the afternoon of 26 January last year and it is believed they were likely to have been killed sometime that evening.

'No memory'

The barrister said Ms Donnison had killed the children at her rented house in Lightwater and then driven to Heathfield, parked the car and gone into the former family home armed with two kitchen knives.

Image caption
The court heard Ms Donnison was a narcissist with an overdeveloped sense of self-importance

Ms Laing said: "We suggest the purpose of her doing so was that having informed Paul Donnison of the deaths of the children the defendant also intended to kill him and no doubt blame him for killing the children."

However she added that Mr Donnison was not at the house and did not return that night or the next morning.

On the morning of 27 January, Ms Donnison went to Heathfield police station and told officers she had killed her children.

She would not tell them where they were but a search of the area soon located them to the boot of the car.

"She claims to have no memory at all of the events that led to the killing of Harry and Elise," Ms Laing said.

The barrister said Ms Donnison will claim she was suffering from depression and was not in her right mind at the time of the killings, and that the charges should be reduced to manslaughter.